JP2003174214A - Magnetoresistive effect film, its manufacturing method and storage device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the phenomenon that the magnitude of an external magnetic field necessary for magnetization inversion is different depending on magnetization inversion direction, in a magnetoresistive effect film using magnetic material showing vertical magnetization. <P>SOLUTION: A first magnetic material 111 exhibiting vertical magnetization, a nonmagnetic conductor film 114, a second magnetic material 112 exhibiting vertical magnetization, a nonmagnetic dielectrics film 115 and a third magnetic material 113 exhibiting vertical magnetization are stacked in this order. Magnetization of the first magnetic material 111 and magnetization of the third magnetic material 113 are anti-parallel with one another. The second magnetic material 112 has a relatively small magnetization inversion magnetic field as compared with the first magnetic material 111 and the third magnetic material 113. The direction of a static magnetic coupling force which is applied from the first magnetic material 111 to the second magnetic material 112 is reverse to the direction of a static magnetic coupling force which is applied from the third magnetic material 113 to the second magnetic material 112, and magnitude of the static magnetic coupling forces are almost equal. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive effect film using a magnetic material exhibiting perpendicular magnetization, and more particularly to a magnetic resistance reduction phenomenon in which the magnitude of an externally applied magnetic field required for magnetization reversal varies depending on the magnetization reversal direction. The present invention relates to a resistance effect film and a memory using such a magnetoresistive film.

[0002]

2. Description of the Related Art In recent years, a semiconductor memory, which is a solid-state memory, has been widely used in information equipment, such as DRAM (dynamic random access memory) and FeRAM.
There are various types such as (ferroelectric random access memory) and flash EEPROM (electrically erasable programmable read only memory). The characteristics of these semiconductor memories have advantages and disadvantages, and there is no memory satisfying all the specifications required in the current information equipment. For example, a DRAM has a high recording density and a large number of rewritable times, but it is volatile and the stored information is lost when the power is turned off. On the other hand, flash EEPRO
Although M is non-volatile, it takes a long time to erase information and is not suitable for high-speed information processing.

In contrast to the current state of the semiconductor memory as described above, a memory (MRAM; magnetic random access memory) using the magnetoresistive effect is non-volatile, and has a writing time, a reading time, a recording density, and a rewriting. It is promising as a memory that satisfies all the specifications required by many information devices in terms of the number of possible times and power consumption.
In particular, spin-dependent tunnel magnetoresistance (TMR; Tunnel Mag)
The MRAM utilizing the neto-Resistance) effect is advantageous for high recording density or high-speed reading because a large read signal can be obtained, and its feasibility as an MRAM has been proved in recent research reports.

The basic structure of a magnetoresistive effect film used as an element of an MRAM is a sandwich structure in which a magnetic layer is formed adjacent to both sides of a nonmagnetic layer. As a material often used for the non-magnetic layer, Cu or Al ₂ O _{3 is used.}
Is mentioned. Cu in the non-magnetic layer in the magnetoresistive film
The one using a conductor such as a giant magnetoresistive effect (G
MR; Giant Magneto-Resistance) film, Al ₂ O ₃
The one using an insulator such as is called a spin-dependent tunnel magnetoresistive (TMR) film. Generally, the TMR film is GM
It exhibits a larger magnetoresistive effect than the R film.

12A and 12B show a magnetoresistive film having a structure in which two magnetic layers, which are in-plane magnetized films, are laminated with a nonmagnetic layer interposed therebetween. The direction of magnetization is indicated by the arrow. 2 as shown in FIG.
When the magnetization directions of the two magnetic layers are parallel, the electric resistance of the magnetoresistive film (electric resistance between one magnetic layer and the other magnetic layer) is relatively small, as shown in FIG. When the magnetization directions are antiparallel, the electric resistance becomes relatively large. Therefore, it is possible to read information by utilizing the above properties. For example, when the magnetic layer 13 located above the non-magnetic layer 12 is a memory layer and the magnetic layer 11 located below is a detection layer, "1" is set when the magnetization direction of the memory layer (magnetic layer 13) is rightward, and leftward In case of, it is set to "0".

As shown in FIG. 13A, both magnetic layers 11,
When the magnetization directions of 13 are both rightward in the drawing, the electric resistance of the magnetoresistive film is relatively small, and the magnetization direction of the detection layer 11 is rightward in the drawing and the magnetization direction of the memory layer 13 as shown in FIG. 13B. However, if it is facing left in the figure, the electric resistance is relatively large. Similarly, as shown in FIG. 13C, when the magnetization direction of the detection layer 11 is leftward and the magnetization direction of the memory layer 13 is rightward, the electric resistance is relatively large, and FIG.
As shown in (d), when the magnetization directions of both magnetic layers 11 and 13 are leftward, the electric resistance is relatively small. That is, when the magnetization direction of the detection layer 11 is fixed to the right, if the electric resistance is relatively large, “0” is recorded in the memory layer 13, and the electric resistance is relatively large. If it is small, "1" is recorded.
Alternatively, when the magnetization direction of the detection layer 11 is fixed to the left, if the electric resistance is relatively large, “1” is recorded in the memory layer 13, and the electric resistance is relatively large. If it is small, "0" is recorded.

Therefore, the composition of each magnetic layer 11, 13 is selected so that the coercive force of the detection layer 11 is relatively large and the coercive force of the memory layer 13 is relatively small, and the detection layer 11 is magnetized in one direction. Then, by adding magnetization to the memory layer 13 to the extent that magnetization reversal of the detection layer 11 does not occur and changing the direction of magnetization of the memory layer 13, it becomes possible to record information on the magnetoresistive film. Also, the recorded information can be read by detecting the electric resistance of the magnetoresistive film.

When the element size of the magnetoresistive effect film is reduced in order to increase the recording density of the MRAM, in the MRAM using the in-plane magnetized film as the magnetic layer, there is an influence such as demagnetizing field or curling of the magnetization of the element end face. Therefore, there arises a problem that information cannot be held. In order to avoid this problem, for example, the shape of the magnetic layer may be rectangular. However, this method cannot reduce the element size, and therefore the improvement in recording density cannot be expected so much.

Therefore, the present applicant has already proposed to avoid the above problem by using a perpendicular magnetization film, as described in, for example, Japanese Unexamined Patent Publication No. 11-213650. When the perpendicular magnetization film is used, the demagnetizing field does not increase even when the element size is reduced, so that a magnetoresistive effect film having a smaller size than the MRAM using the in-plane magnetization film can be realized.

In the magnetoresistive effect film using the perpendicular magnetization film,
Similar to the magnetoresistive effect film using the in-plane magnetized film, the electric resistance of the magnetoresistive effect film is relatively small when the magnetization directions of the two magnetic layers are parallel, and the electric resistance when the magnetization directions are antiparallel. Is relatively large. The magnetic layer 23 located above the non-magnetic layer 22 is used as a memory layer, and the magnetic layer 21 located below is used as a detection layer. The magnetization direction of the memory layer 23 is "1" when the magnetization direction is upward, and "0" when the magnetization direction is downward. And As shown in FIG. 14A, when the magnetization directions of both magnetic layers 21 and 23 are upward, the electric resistance of the magnetoresistive effect film is relatively small, and FIG.
As shown in FIG. 4C, when the magnetization direction of the detection layer 21 is downward and the magnetization direction of the memory layer 23 is upward, the electric resistance becomes relatively large. Similarly, as shown in FIG. 14B, the magnetization direction of the detection layer 21 is upward and the memory layer 23 is
The electric resistance becomes relatively large when the magnetization direction is downward, and the electric resistance becomes relatively small when the magnetization directions of both magnetic layers 21 and 23 are downward as shown in FIG. That is, when the magnetization direction of the detection layer 21 is fixed upward, if the electric resistance is relatively large, "0" is recorded in the memory layer 23, and the electric resistance is relatively large. If it is smaller, "1" is recorded. Alternatively, when the magnetization direction of the detection layer 21 is fixed downward, if the electric resistance is relatively large, "1" is recorded in the memory layer 23, and the electric resistance is relatively large. If it is small, "0" is recorded.

[0011]

As described above, in the magnetoresistive effect film, at least two magnetic materials are several Å to several nm.
Has a structure that is laminated through the thin non-magnetic film of
Both magnetic bodies are magnetostatically coupled to each other by the magnetic field generated from each magnetic body. For example, in a magnetoresistive effect film using a magnetic body exhibiting perpendicular magnetization, when changing from the magnetization state of FIG. 14A to the state of FIG. 14C or from the state of FIG. 14D to the state of FIG. When the magnetization directions of both magnetic bodies are changed from the parallel state to the antiparallel state as in the case of, the magnetic field generated from the memory layer 23 acts so as to prevent the magnetization reversal of the detection layer 21. An externally applied magnetic field larger than the magnetization reversal magnetic field at that time is required. On the contrary, the magnetization directions of both magnetic bodies are changed as in the case of changing from the magnetization state of FIG. 14C to the state of FIG. 14A and from the state of FIG. 14B to the state of FIG. When the anti-parallel state is changed to the parallel state, the magnetic field generated from the memory layer 23 works to assist the magnetization reversal of the detection layer 21, and thus the detection layer 21.
Can be reversed with an externally applied magnetic field smaller than the magnetization reversal magnetic field in the case of the single layer.

As a means for recording (writing) data in the MRAM, it is generally considered that a conductor wire is arranged in the vicinity of the MRAM, a current is passed through the conductor wire, and a magnetic field generated by the current is used. There is. In this configuration, the magnitude of the magnetic field applied to the MRAM is proportional to the magnitude of the current flowing through the conductor, but there is a limit to the current density that can be passed through the conductor, and due to restrictions such as power supply capacity, each The magnetization reversal field of the magnetic material is preferably as small as possible. However, as described above, in the case of the conventional magnetoresistive effect film, there is a problem to be solved that a relatively large magnetic field is required when the magnetization directions of the magnetic bodies change from the parallel state to the antiparallel state.

The present invention has been made in view of this point, and is a magnetoresistive effect film using a magnetic body exhibiting perpendicular magnetization, and the magnitude of an externally applied magnetic field required for magnetization reversal depends on the magnetization reversal direction. An object of the present invention is to provide a magnetoresistive effect film in which different phenomena are reduced, and a memory using such a magnetoresistive effect film.

[0014]

The magnetoresistive effect film of the present invention comprises a first magnetic body exhibiting perpendicular magnetization, a nonmagnetic conductor film, and
It has a structure in which a second magnetic body exhibiting perpendicular magnetization, a non-magnetic dielectric film, and a third magnetic body exhibiting perpendicular magnetization are laminated in this order, and the magnetization of the first magnetic body and the third magnetic body are laminated. The magnetization of the magnetic material is antiparallel to each other, and the second magnetic material has a relatively small magnetization reversal magnetic field as compared with the first magnetic material and the third magnetic material.

The magnetoresistive film of the present invention is typically composed of
It shows a spin tunneling effect when an electric current is passed in the direction perpendicular to the film surface.
In this magnetoresistive effect film, the magnetostatic coupling force exerted on the second magnetic body by the first magnetic body and the magnetostatic coupling force exerted on the second magnetic body by the third magnetic body are adjusted to adjust the second magnetic body. The difference between the magnitude of the externally applied magnetic field required to orient the magnetization direction of the magnetic substance from the first direction to the second direction and the magnitude of the externally applied magnetic field required to orient the magnetization direction of the second direction from the second direction. Can be made smaller.

In the present invention, from the first magnetic body to the second magnetic body
It is preferable that the magnitude of the magnetostatic coupling force exerted on the magnetic body and the magnitude of the magnetostatic coupling force exerted on the second magnetic body from the third magnetic body are substantially equal.

In the present invention, the interface between the first magnetic body and the non-magnetic conductor film, the interface between the second magnetic body and the non-magnetic conductor film, and the interface between the second magnetic body and the non-magnetic dielectric film. It is preferable to form a magnetic material having a large spin polarization on at least one of the interface and the interface between the third magnetic material and the nonmagnetic dielectric film. In this case, it is more preferable to form a plurality of magnetic bodies having large spin polarizability so as to be symmetrical with respect to the second magnetic body in the film thickness direction of the magnetoresistive effect film. An example of such a magnetic substance having a large spin polarization is an alloy of Fe and Co.

In the magnetoresistive film of the present invention, the first
The magnetic substance and the third magnetic substance may have the same composition. Further, the first magnetic body and the third magnetic body may have the same shape and size, and the nonmagnetic conductor film and the nonmagnetic dielectric film may have the same film thickness.

In such a magnetoresistive film of the present invention, the nonmagnetic dielectric film is made of, for example, Al ₂ O ₃ . The first magnetic body, the second magnetic body, and the third magnetic body are selected from, for example, Gd, Dy, and Tb.
The main component is one or more kinds of rare earth metal elements and one or more kinds of transition metal elements selected from Fe, Co, and Ni.

In the method of manufacturing a magnetoresistive effect film of the present invention, when manufacturing the above-described magnetoresistive effect film, one of the magnetic properties of the first magnetic body and the third magnetic body is applied while applying a magnetic field in one direction. While forming the body, while applying a magnetic field in the direction opposite to the magnetic field direction applied when forming the one magnetic body,
The other magnetic body of the first magnetic body and the third magnetic body is formed.

The memory of the present invention comprises the above-mentioned magnetoresistive film of the present invention, and means for recording on the magnetoresistive film.
Means for reading information recorded on the magnetoresistive film.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Next, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic sectional view showing the structure of a magnetoresistive effect film according to an embodiment of the present invention. The illustrated magnetoresistive film is a first magnetic body 111 that is a perpendicular magnetization film.
A second magnetic body 112 which is a perpendicular magnetization film and a third magnetic body 113 which is a perpendicular magnetization film are provided in this order, and the first magnetic body 111 and the second magnetic body 112 are provided. Non-magnetic conductor film 114 that is non-magnetic and has electrical conductivity between
And a non-magnetic dielectric film 115 made of a non-magnetic dielectric is disposed between the second magnetic body 112 and the third magnetic body 113. Here, the magnetization directions of the first magnetic body 111 and the third magnetic body 113 are antiparallel to each other. In this case, the magnetization of the first magnetic body 111 may be upward and the magnetization of the third magnetic body 113 may be downward, as shown in FIG. 1A, or FIG.
As shown in FIG.
The magnetization of the magnetic body 113 may be upward. Although the magnetization direction of the second magnetic body 112 is not shown in FIG. 1, the magnetization direction of the second magnetic body 112 is either upward or downward in the drawing depending on the data written in the perpendicular magnetic effect film. Become.

As described above, when the magnetization directions of the first magnetic body 111 and the third magnetic body 113 are antiparallel,
The magnetostatic coupling force acting between the third magnetic body 113 and the second magnetic body 112 cancels out the magnetostatic coupling force acting between the first magnetic body 111 and the second magnetic body 112. Since they work in the same direction, the magnetization direction of the second magnetic body 112 is reversed by a magnetic field of the same magnitude when the magnetization direction of the second magnetic body 112 is reversed from upward to downward and vice versa. It becomes possible.

The first magnetic body 111 and the second magnetic body 112
As the perpendicularly magnetized film used as the third magnetic body 113, an artificial lattice film of noble metal-transition metal, CoCr, or the like.
Alternatively, a rare earth metal-transition metal artificial lattice film or an alloy thereof may be used. Among these perpendicularly magnetized films, the rare earth metal-transition metal alloy is easy to make the squareness ratio of the magnetization curve to 1 and is easy to prepare. Is preferred as a magnetic material for As the rare earth metal in the rare earth metal-transition metal alloy, one or more elements selected from Gd, Dy and Tb,
As the transition metal, one or more elements selected from Co, Fe and Ni are preferably used. In particular, Gd is preferable as the rare earth metal used for the second magnetic body 112 that requires a small magnetization reversal magnetic field.

Various materials are used for the non-magnetic conductor film 114.
Can be used, for example, Pt, Au, Ag, Ru, Z
n, Si, In, Sn, Pb, Ta, Ti, W, Cu,
Many materials such as Al can be used. Also non-magnetic
The dielectric film 115 has SiO ₂, Al₂O₃Can be used
Although it is possible, it is possible to obtain a large magnetoresistance change.
l₂O₃Is preferably used. Magnetoresistance effect shown here
The film allows a current to flow in the direction perpendicular to the film surface, and the non-magnetic dielectric film 11
By spin-dependent tunneling of electrons in 5
It is recorded on this magnetoresistive film using the generated magnetoresistance.
However, the magnetoresistance change is non-
The interface between the magnetic conductor film 114 and the magnetic bodies 111 and 112, and
Due to the spin-dependent scattering that occurs in the magnetic substances 111 to 113,
Even happens. However, the magnetic resistance due to spin-dependent scattering
Anti-change is magneto-resistance change due to spin-dependent tunneling
It is significantly smaller than
Inferred magnetoresistance change is due to spin-dependent tunneling
It can be thought that it is a thing, and the magnetoresistance change due to spin-dependent scattering
Can be ignored.

By the way, the magnetoresistive effect film using the rare earth metal-transition metal alloy has a smaller magnetoresistive change rate than the magnetoresistive effect film using only the transition metal. this is,
It is considered that this is because the rare earth metal at the interface with the non-magnetic dielectric film does not have a large spin polarizability. Therefore, as proposed in Japanese Patent Laid-Open No. 2000-306374,
It is possible to increase the magnetoresistance change rate by exchange-coupling a magnetic substance having a high spin polarizability (a magnetic substance having a high spin polarizability) with a magnetic substance composed of a rare earth metal and a transition metal. Examples of the magnetic substance having a large spin polarizability include transition metals such as Fe, Co, and alloys thereof.
The eCo alloy is preferable because it has a large spin polarizability.
However, since the transition metal thin film does not exhibit perpendicular magnetization, it is necessary to take measures such as directing the magnetization in the direction perpendicular to the film surface by exchange coupling with the perpendicular magnetization film. Such a film configuration is
It can also be used in the magnetoresistive film of the present invention. The magnetoresistive effect film according to the present invention, in which the high spin polarizability magnetic material is interposed as a thin layer, will be described below.

The magnetoresistive film shown in FIG. 2 is different from the magnetoresistive film shown in FIG. 1 in that the high spin polarizability magnetic substance 120 is provided between the non-magnetic dielectric film 115 and the third magnetic substance 113.
Is arranged. On the other hand, the magnetoresistive effect film shown in FIG. 3 is the same as the magnetoresistive effect film shown in FIG. 1, except that the high spin polarizability magnetic substance 119 is disposed between the second magnetic substance 112 and the non-magnetic dielectric film 115. Is. As described above, the high spin polarizability magnetic substance is used for the non-magnetic dielectric film 115 and the magnetic substance 1.
It can be placed at either interface with 12, 113. Further, as shown in FIG. 4, the non-magnetic dielectric film 11
The high spin polarizability magnetic materials 119 and 120 can be provided on the upper and lower surfaces of the magnetic field magnet No. 5, and by arranging the high spin polarizability magnetic materials on both surfaces in this way, a larger magnetoresistance change can be obtained.

By the way, Fe, Co or FeCo alloy has a relatively large magnetization. Therefore, when the high spin polarizability magnetic material is provided on the interface of the non-magnetic dielectric film as described above, the magnetostatic coupling force exerted by the magnetic material on the second magnetic material 112 cannot be ignored. As a method for solving this problem, a high spin polarizability magnetic body is formed at a position symmetrical with respect to the second magnetic body with respect to the high spin polarizability magnetic body arranged in contact with the non-magnetic dielectric film, Two
Of these high spin polarizability magnetic materials arranged at positions symmetrical to each other, the magnetostatic coupling forces in opposite directions act on the second magnetic material 112, and apparently It is possible to prevent the magnetostatic coupling force from acting on the second magnetic body 112. Hereinafter, the magnetoresistive effect film in which the high spin polarizability magnetic material is arranged at the symmetrical position with respect to the second magnetic material 112 will be described.

The magnetoresistive film shown in FIG. 5 is the same as the magnetoresistive film shown in FIG. 2, except that a high spin polarizability magnetic substance 117 is arranged between the non-magnetic conductor film 114 and the first magnetic substance 111. And the high spin polarizability magnetic materials 117, 12
0 exists in the mutually symmetrical position with respect to the second magnetic body 112. The magnetoresistive film shown in FIG.
In the magnetoresistive effect film shown in FIG. 1, the high spin polarization magnetic material 11 is provided between the non-magnetic conductor film 114 and the second magnetic material 112.
8 are arranged, and the high spin polarizability magnetic substance 11
8, 119 are located at positions symmetrical to each other with respect to the second magnetic body 112. Further, in the magnetoresistive effect element shown in FIG. 7, in the magnetoresistive effect film shown in FIG. 4, a high spin polarizability magnetic substance 117 is arranged between the non-magnetic conductor film 114 and the first magnetic substance 111, and A high spin polarization magnetic material 118 is disposed between the non-magnetic conductor film 114 and the second magnetic material 112, and the high spin polarization magnetic materials 117 and 118 and the high spin polarization magnetic materials 120 and 11 are provided.
9 means that the second magnetic body 112 exists at positions symmetrical to each other.

In the magnetoresistive film of the present invention, the magnetostatic coupling force between the first magnetic body 111 and the second magnetic body 112 and the magnetostatic coupling force between the third magnetic body 113 and the second magnetic body 112. Although it is required that the values of and are approximately the same in the opposite direction, it is preferable that the balance be maintained even if the temperature of the magnetoresistive film changes. Such characteristics are, for example,
This can be easily realized by forming the first magnetic body 111 and the third magnetic body 113 in exactly the same manner. In other words, if the magnetic substances have the same composition, the temperature change of the magnetization is the same. Therefore, the magnetostatic coupling force between the magnetic substances 111 and 113 and the second magnetic substance 112 is balanced even if the temperature changes. It won't collapse.

Further, the magnetoresistive effect film of the present invention is used as a memory element, and means for recording information on the magnetoresistive effect film (memory element) and means for reading information recorded on the magnetoresistive effect film are provided. As a result, it is possible to configure a memory that consumes less current and requires less power during writing. Here, as a means for recording information, a magnetic field generated by passing a current through a wiring is preferably used, and as a means for reading the recorded information, a constant current is passed through the memory element. A circuit that detects the voltage at both ends is preferably used.

[0033]

EXAMPLES Next, regarding the magnetoresistive effect element of the present invention,
A more detailed description will be given based on examples.

(Example 1) A magnetoresistive film having the structure shown in FIG. 1 was prepared. A Si wafer (silicon substrate) is used as a substrate, and a third wafer is formed on the substrate in a film forming container.
As a magnetic substance 113 of Tb ₂₀ (Fe ₆₀
Co ₄₀ ) ₈₀ film is formed by the sputtering method, and further Al ₂
A nonmagnetic dielectric film 115 having a film thickness of 1.5 nm was formed by a sputtering method using an O ₃ target. The obtained film is plasma-oxidized in an oxygen atmosphere to obtain a non-magnetic dielectric film 115.
After making the non-magnetic dielectric film 115 to have a composition of Al ₂ O ₃ by compensating for the oxygen atoms that are deficient in, the second magnetic body 112 is evacuated sufficiently to form Gd ₂₁ ( Fe ₆₀ Co ₄₀ ) ₇₉ film, an Al film having a thickness of 1.5 nm as the non-magnetic conductor film 114, and the first magnetic body 11
1 as Tb ₂₀ (Fe ₆₀ Co ₄₀ ) with a film thickness of 30 nm
_{An 80} film and a 2 nm Pt film as a protective film were sequentially formed by a sputtering method. However, during the film formation of the first magnetic body 111 and the third magnetic body 113, a magnetic field is applied in a direction perpendicular to the substrate so that the magnetic bodies 111 and 113 are magnetized in a predetermined direction. did. That is, the direction of the magnetic field applied during the film formation of the first magnetic body 111 and the third magnetic body 1
The directions of the magnetic fields applied during the film formation of 13 were antiparallel to each other, and the magnitude of the applied magnetic field was set to a value smaller than the magnetization reversal magnetic field of the third magnetic body 113. By applying a magnetic field during film formation in this way, it was possible to make the magnetization directions of the first magnetic body 111 and the third magnetic body 113 antiparallel to each other.

Next, a 0.5 μm square resist film was formed on the thus obtained multilayer film, and the multilayer film in a portion not covered with the resist was removed by dry etching. After etching, a 100 nm thick Al ₂ O ₃ film is formed.
A film was formed by a sputtering method, and the resist and the Al ₂ O ₃ film on the resist were removed to form an insulating film for electrically insulating the upper electrode and the Si wafer. After that, an upper electrode is formed by an Al film by a lift-off method, and an Al ₂ O ₃ film in a portion not covered by the upper electrode is partially removed to form an electrode pad for connecting a measurement circuit,
The magnetoresistive effect film was completed.

The upper electrode and the lower electrode (S
A constant current power supply is connected between the i-wafer and the i-wafer) and a constant current is caused to flow so that electrons tunnel through the Al ₂ O ₃ film of the non-magnetic dielectric film 115, and a magnetic field is applied in a direction perpendicular to the film surface of the magnetoresistive film. Was applied to change the size and the direction, and the change in the voltage of the magnetoresistive film (magnetoresistance curve) was measured. However, the magnitude of the applied magnetic field is smaller than the magnetization reversal magnetic field of the first magnetic body 111 and the third magnetic body 113, the magnetization directions of both magnetic bodies 111 and 113 are fixed, and the second magnetic body 112 is fixed. The size is such that only the magnetization direction of can be changed. According to the measurement results, almost no difference was observed between the magnitude of the externally applied magnetic field when the voltage applied to the magnetoresistive film was lowered and the magnitude of the externally applied magnetic field when the voltage was increased. That is, it was found that in this magnetoresistive film, the phenomenon that the magnitude of the externally applied magnetic field required for magnetization reversal varies depending on the magnetization reversal direction.

(Example 2) A magnetoresistive film having the structure shown in FIG. 7 was prepared. A Si wafer (silicon substrate) is used as a substrate, and a third wafer is formed on the substrate in a film forming container.
As a magnetic substance 113 of Tb ₂₀ (Fe ₆₀
Co ₄₀ ) ₈₀ film, 1 n as high spin polarizability magnetic substance 120
A Fe ₆₀ Co ₄₀ film having a film thickness of m was sequentially formed by a sputtering method, and a nonmagnetic dielectric film 115 having a film thickness of 1.5 nm was further formed by a sputtering method using an Al ₂ O ₃ target. The obtained film is plasma-oxidized in an oxygen atmosphere, and the non-magnetic dielectric film 115 is made to have a composition of Al ₂ O ₃ by supplementing oxygen atoms that are missing in the non-magnetic dielectric film 115. After vacuuming, an Fe ₆₀ Co ₄₀ film having a film thickness of 1 nm is formed as the high spin polarizability magnetic substance 119, and a Gd ₂₁ (Fe ₆₀ C film having a film thickness of 50 nm is formed as the second magnetic substance 112.
o ₄₀ ) ₇₉ film, 1 nm as high spin polarizability magnetic material 118
Fe ₆₀ Co ₄₀ film and non-magnetic conductor film 114 of 1.5
nm Al film, high spin polarizability magnetic substance 117 having a thickness of 1 nm Fe ₆₀ Co ₄₀ film, and first magnetic substance 111 having a thickness of 30 nm Tb ₂₀ (Fe ₆₀ Co ₄₀ ).
_{An 80} film and a 2 nm Pt film as a protective film were sequentially formed by a sputtering method.

At this time, during the film formation of the first magnetic material 111 and the third magnetic material 113, a magnetic field is applied in a direction perpendicular to the substrate so that these magnetic materials 111 and 113 move in a predetermined direction. I tried to magnetize it. That is, the first magnetic body 1
Direction of magnetic field applied during film formation of 11 and third magnetic body 11
The directions of the magnetic fields applied during the film formation of No. 3 were antiparallel to each other, and the magnitude of the applied magnetic field was smaller than the magnetization reversal field of the third magnetic body 113. By applying a magnetic field during film formation in this way, it was possible to make the magnetization directions of the first magnetic body 111 and the third magnetic body 113 antiparallel to each other. Further, the high spin polarizability magnetic body 120 is the third magnetic body 113, the high spin polarizability magnetic body 117 is the first magnetic body 111, and the high spin polarizability magnetic body 1 is further.
18, 119 and the second magnetic body 112 are exchange-coupled with each other, and the magnetizations of the high spin polarizability magnetic bodies 117 to 120 are oriented in the direction perpendicular to the film surface. Here, the high spin polarizability magnetic materials 119 and 120 are formed in order to obtain a high magnetoresistance change rate.
Reference numerals 17 and 118 denote magnetic layers for adjusting the magnetostatic coupling force, and do not affect the spin polarizability.

Next, a 0.5 μm square resist film was formed on the thus-obtained multilayer film, and the multilayer film in a portion not covered with the resist was removed by dry etching. After etching, 120 nm thick Al ₂ O ₃
A film was formed by a sputtering method, and the resist and the Al ₂ O ₃ film on the resist were removed to form an insulating film for electrically insulating the upper electrode and the Si wafer. After that, an upper electrode is formed by an Al film by a lift-off method, and an Al ₂ O ₃ film in a portion not covered by the upper electrode is partially removed to form an electrode pad for connecting a measurement circuit,
The magnetoresistive effect film was completed.

The upper electrode and the lower electrode (S
A constant current power supply is connected between the i-wafer and the i-wafer) and a constant current is caused to flow so that electrons tunnel through the Al ₂ O ₃ film of the non-magnetic dielectric film 115, and a magnetic field is applied in a direction perpendicular to the film surface of the magnetoresistive film. Was applied to change the size and the direction, and the change in the voltage of the magnetoresistive film (magnetoresistance curve) was measured. However, the magnitude of the applied magnetic field is smaller than the magnetization reversal magnetic field of the first magnetic body 111 and the third magnetic body 113, the magnetization directions of both magnetic bodies 111 and 113 are fixed, and the second magnetic body 112 is fixed. The size is such that only the magnetization direction of can be changed. According to the measurement results, almost no difference was observed between the magnitude of the externally applied magnetic field when the voltage applied to the magnetoresistive film was lowered and the magnitude of the externally applied magnetic field when the voltage was increased. That is, it was found that in this magnetoresistive film, the phenomenon that the magnitude of the externally applied magnetic field required for magnetization reversal varies depending on the magnetization reversal direction.

(Embodiment 3) After forming a transistor, a wiring layer, etc. on a Si wafer, a magnetoresistive effect film having the film structure used in Embodiment 2 is formed, and the magnetoresistive effect film is formed into 9 memories in 3 rows and 3 columns. The device was processed into a memory cell array. Information is recorded on the memory element by a magnetic field generated by passing an electric current through the conductive wire. An electric circuit for applying the recording magnetic field is shown in FIG. 8 and a read circuit is shown in FIG. 8 and 9 correspond to views of the Si wafer as viewed from above, and the magnetization direction in the magnetoresistive film is perpendicular to the paper surface. In practice, the configurations shown in FIGS. 8 and 9 are formed so as to overlap each other in the memory cell array by the multilayer wiring technique.

A method of selectively reversing the magnetization of the magnetic film of the selected memory element (magnetoresistive film) will be described.

As shown in FIG. 8, nine memory elements (magnetoresistive films) 101 to 109 are arranged in a 3 × 3 array in the memory cell array, and each row of memory elements is sandwiched in the row direction. First write lines 311 to 314 extending are provided. The left ends of the write lines 311 to 314 in the drawing are connected in common, and the right ends of the write lines 311 to 314 are connected to the transistors 300 to 211 for connecting the write lines 311 to 314 to the power supply 411 and the wiring 300, respectively. Transistors 215 to 218 are provided. Second write lines 321 to 324 extending in the column direction are provided so as to sandwich each column of memory elements.
The upper ends of the write lines 321 to 324 in the figure are connected in common, and the lower ends of the figure are transistors 219 to 222 for grounding the write lines 321 to 324, respectively.
Transistor 22 for connecting to each wiring 300
3 to 226 are provided.

Here, for example, when the magnetization of the magnetoresistive effect film 105 is selectively reversed, the transistors 212 and 2 are used.
17, 225 and 220 are turned on, and the other transistors are turned off. In this way current flows through the write lines 312, 313, 323, 322 and induces a magnetic field around them. In this state, magnetic fields in the same direction are applied to the magnetoresistive effect film 105 only from the four write lines, and magnetic fields in the same direction are applied to the other magnetoresistive effect films only from the two write lines. Further, a magnetic field in the opposite direction is applied to cancel the magnetic field effectively, so that the magnetic field is not applied as much as the magnetoresistive film 105. Therefore, if the combined magnetic field when magnetic fields are applied in the same direction from the four write lines is adjusted to be slightly larger than the magnetization reversal magnetic field of the magnetic film of the memory element (magnetoresistive film), Selective magnetoresistive film 1
Only the magnetization of 05 can be reversed. In addition, a magnetic field in the direction opposite to that described above is applied to the magnetoresistive film 1.
When applied to 05, transistors 213, 216, and
224 and 221 are turned on, and other transistors are turned off. By doing so, the current flows through the write lines 312, 313, 323, 322 in the opposite direction to the above, and the magnetic field in the opposite direction is applied to the magnetoresistive effect film 105. Therefore, binary information different from the above is recorded on the magnetoresistive film 105.

Next, the read operation will be described. As shown in FIG. 9, each memory element (magnetoresistive effect film) 101 to
Transistors 231 to 239 for grounding the memory element are formed in series at one end of 109, respectively. The bit lines 331 to 333 are provided for each row, and the bit lines 331 to 333 are connected to the right end of the bit lines 331 to 333 in the figure via a fixed resistor 150.
The transistors 240 to 242 are provided for connecting to 2. The bit line 331 is the magnetoresistive film 101-
The bit line 332 is connected to the other end of the magnetoresistive effect films 104 to 106, and the bit line 333 is connected to the other end of the magnetoresistive effect films 107 to 109. The left ends of the bit lines 331 to 333 in the drawing are commonly connected and connected to a sense amplifier 500 that amplifies the difference between the potential of these bit lines and the reference voltage Ref. In addition, the word line 34
1 to 343 are provided for each column, and the word line 341
Is connected to the gates of the transistors 231, 234, 237, and the word line 342 is connected to the transistors 232, 235, 2
38 and the word line 343 is connected to the gates of transistors 233, 236, 239.

Here, for example, it is considered to read out the information recorded on the magnetoresistive effect film 105. In this case, the transistors 235 and 241 are turned on. Then,
Power supply 412, fixed resistance 150, and magnetoresistive film 105
Are connected in series. Therefore, the power supply voltage is divided into respective resistances at a ratio of the resistance value of the fixed resistance 150 and the resistance value of the magnetoresistive effect film 105. Since the power supply voltage is fixed, when the resistance value of the magnetoresistive effect film changes, the voltage applied to the magnetoresistive effect film changes accordingly. By reading this voltage value with the sense amplifier 500, the information recorded in the magnetoresistive effect film 105 can be read.

FIG. 10 schematically shows the three-dimensional structure of one peripheral portion of such a memory element. Here, the vicinity of the magnetoresistive film 105 in FIGS. 8 and 9 is shown. For example, two n-type diffusion regions 162 and 163 are formed on a p-type Si substrate 161, and a word line (gate electrode) 3 is interposed between them by an insulating layer 323.
42 is formed. The ground line 356 is connected to the n-type diffusion region 162 via the contact plug 351, and the magnetoresistive film 105 is connected to the n-type diffusion region 163 via the contact plugs 352, 353, 354, 357 and the local wiring 358. . The magnetoresistive effect film 105 is further connected to the bit line 332 via a contact plug 355. Next to the magnetoresistive film 105, write lines 322 and 323 for generating a magnetic field are arranged.

(Embodiment 4) After forming a transistor, a wiring layer and the like on a Si wafer, a magnetoresistive effect film having the film structure used in Embodiment 2 is formed, and the magnetoresistive film is formed into 9 memories of 3 rows and 3 columns. The device was processed into a memory cell array. The circuit configuration of this memory including such a memory cell array is shown in FIG. In this memory, information recording is performed by applying an in-plane magnetic field and a vertical magnetic field to a desired memory element. Here, the in-plane magnetic field is generated by passing a current through the bit line. In the memory cell array of the third embodiment, the circuit for writing information and the circuit for reading are electrically separated, whereas the memory cell array of the fourth embodiment is different from the circuit for writing. The bit line is shared with the circuit for reading.

FIG. 1 shows a configuration for recording information.
As shown in FIG. 1, nine memory elements (magnetoresistive effect films) 101 to 109 are arranged in a 3 × 3 array in the memory cell array, and write lines 611 extending in the column direction sandwiching each row of the memory elements. ~ 614 are provided. The upper ends of these write lines 611 to 614 are connected in common, and the lower ends of these lines are respectively connected to the write lines 611.
To transistor 614 for connecting ~ 614 to power supply 411
11 to 514 and transistors 515 to 518 for connecting to the wiring 600 are provided.

As a structure for reading information, each memory element (magnetoresistive film) 101-109.
Transistors 531 to 539 for grounding the memory element are formed in series at one end of each.
Bit lines 631 to 633 are provided for each row, and transistors 540 to 540 for connecting these bit lines 631 to 633 to the power supply 412 via the fixed resistor 150 are provided at the right ends of the bit lines 631 to 633 in the figure, respectively. 542
And transistors 521 to 523 for connecting these bit lines 631 to 633 to the wiring 600. The bit line 631 is connected to the other ends of the magnetoresistive effect films 101 to 103, and the bit line 632 is connected to the magnetoresistive effect film 104.
To 106, and the bit line 633 is connected to the other ends of the magnetoresistive films 107 to 109. Bit line 631
The left ends of ˜633 in the drawing are connected in common, and are connected via a transistor 551 to a sense amplifier 500 that amplifies the difference between the potential of these bit lines and the reference voltage Ref.
Further, it is connected to the ground potential through the transistor 624. In addition, word lines 641 to 643 are provided for each column, and the word line 641 includes transistors 531 and 533.
The word line 642 is connected to the gates of the transistors 532, 535, 538, and the word line 643 is connected to the gates of the transistors 533, 536, 539.

A method of selectively reversing the magnetization of the magnetic film of the selected memory element will be described. For example, in the case of selectively reversing the magnetization of the magnetoresistive effect film 105, the transistors 512, 517, 522, and 524 are turned on and the other transistors are turned off. By doing so, the current flows through the write lines 612 and 613, and a magnetic field is applied in a direction perpendicular to the film surface of the magnetoresistive effect film 105. Further, a current also flows through the bit line 632, and the magnetic field generated by the current flows in the magnetoresistive film 10.
It is applied in the in-plane direction to the film surface of No. 5. Therefore, since a magnetic field in the in-plane direction and a relatively large magnetic field in the direction perpendicular to the film plane are applied to the magnetoresistive effect film 105, the magnetization of the magnetoresistive effect film 105 can be reversed. Since no magnetic field is applied to the other magnetoresistive effect films 101 to 104 and 106 to 109 as much as that applied to the magnetoresistive effect film 105, the magnetization direction can be prevented from being reversed. After all, it is possible to reverse the magnetization of only the magnetoresistive film 105 by appropriately setting the magnitude of the current. Further, when a magnetic field in the direction opposite to that described above is applied to the magnetoresistive effect film 105, the transistors 513, 516, 522, and 524 are turned on, and the other transistors are turned off. By doing so, a current flows through the bit line 632 and a magnetic field is applied to the magnetoresistive effect film 105 in the in-plane direction, and at the same time, a current flows through the write lines 613 and 612 in the opposite direction to the above, and the magnetic field is applied. A magnetic field perpendicular to the film surface in the opposite direction is applied to the resistance effect film 105. Therefore, binary information different from the above is recorded on the magnetoresistive film 105.

Next, the operation at the time of reading will be described. For example, it is assumed that the information recorded on the magnetoresistive film 105 is read. In this case, the transistors 535 and 541 are turned on. Then, the power source 412, the fixed resistor 150, and the magnetoresistive film 105 are connected in series. Therefore, the power supply voltage is divided into respective resistances at a ratio of the resistance value of the fixed resistance 150 and the resistance value of the magnetoresistive effect film 105. Since the power supply voltage is fixed, if the resistance value of the magnetoresistive film changes,
The voltage applied to the magnetoresistive film changes. By reading this voltage value with the sense amplifier 500, the information recorded in the magnetoresistive effect film 105 can be read.

(Comparative Example) A magnetoresistive effect film having a structure in which the first magnetic layer was not provided in the magnetoresistive effect film shown in FIG. 4 was prepared. Using a Si wafer as a substrate, in a film forming container,
On this substrate, a Tb ₂₀ (Fe ₆₀ Co ₄₀ ) ₈₀ film having a film thickness of 30 nm was formed as the third magnetic body 113, and the high spin polarization magnetic body 1 was formed.
Fe ₆₀ Co ₄₀ having a film thickness of 1 nm was sequentially formed as a film 20 by a sputtering method, and further, by using an Al ₂ O ₃ target.
A nonmagnetic dielectric film 115 having a film thickness of 5 nm was formed by the sputtering method. The obtained film is plasma-oxidized in an oxygen atmosphere, and the non-magnetic dielectric film 115 is made to have a composition of Al ₂ O ₃ by supplementing oxygen atoms that are missing in the non-magnetic dielectric film 115. A high-spin-polarized magnetic substance 119 is made to have a film thickness of 1 nm by using a Fe ₆₀ Co ₄₀ film, and a second magnetic substance 112 is made to have a film thickness of 50 nm by using Gd ₂₁ (Fe ₆₀ Co ₄₀ ).
_{A 79-} nm film and a 2-nm Pt film as a protective film were sequentially formed by a sputtering method. At this time, the film formation of the third magnetic body 113 is
This was performed while applying a magnetic field smaller than the coercive force of the third magnetic body in the direction perpendicular to the substrate. Further, the high spin polarizability magnetic substance 120 and the high spin polarizability magnetic substance 119 are exchange-coupled with the third magnetic substance 113 and the second magnetic substance 112, respectively. Is oriented in the direction perpendicular to the film surface. Here, the high spin polarizability magnetic bodies 119 and 120 are formed to obtain a high magnetoresistance change rate.

Next, a 0.5 μm square resist film was formed on the thus obtained multilayer film, and the multilayer film in a portion not covered with the resist was removed by dry etching. After etching, an Al ₂ O ₃ film having a thickness of 90 nm is formed by a sputtering method, and the resist and the Al ₂ O ₃ film on the upper part thereof are removed to electrically insulate the upper electrode from the Si wafer. The insulating film of was formed. afterwards,
The upper electrode is made of an Al film by the lift-off method,
The magnetoresistive film of the comparative example was completed as an electrode pad for connecting the measurement circuit by removing a part of the Al ₂ O ₃ film not covered by the upper electrode.

The upper electrode and the lower electrode (S
A constant current power supply is connected between the i-wafer and the i-wafer) and a constant current is caused to flow so that electrons tunnel through the Al ₂ O ₃ film of the non-magnetic dielectric film 115, and a magnetic field is applied in a direction perpendicular to the film surface of the magnetoresistive film. Was applied to change the size and the direction, and the change in the voltage of the magnetoresistive film (magnetoresistance curve) was measured. According to the measurement results, the magnitude of the externally applied magnetic field when the voltage applied to the magnetoresistive film is decreased is about 1.5 kA / m smaller than the magnitude of the externally applied magnetic field when the voltage is increased.
That is, it was found that the phenomenon in which the magnitude of the externally applied magnetic field required for the magnetization reversal differs depending on the magnetization reversal direction is not reduced in this magnetoresistive film.

[0056]

As described above, according to the present invention, in the magnetoresistive effect film, the magnitude of the externally applied magnetic field required for reversing the magnetization direction of the second magnetic body functioning as a memory layer is the magnetization reversal direction. This has the effect of reducing the different phenomena. As a result, by using such a magnetoresistive film, it is possible to obtain a memory in which the current required for writing information can be reduced and the power consumption can be suppressed.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing the structure of a magnetoresistive effect film according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a film configuration of a magnetoresistive effect film of the present invention.

FIG. 3 is a schematic cross-sectional view showing another example of the film configuration of the magnetoresistive effect film of the present invention.

FIG. 4 is a schematic cross-sectional view showing still another example of the film configuration of the magnetoresistive effect film of the present invention.

FIG. 5 is a schematic cross-sectional view showing still another example of the film configuration of the magnetoresistive effect film of the present invention.

FIG. 6 is a schematic cross-sectional view showing still another example of the film configuration of the magnetoresistive effect film of the present invention.

FIG. 7 is a schematic cross-sectional view showing still another example of the film configuration of the magnetoresistive film of the present invention.

FIG. 8 is a circuit diagram showing a circuit for generating a magnetic field applied to record information used in Example 3;

FIG. 9 is a circuit diagram showing a circuit for reading recorded information used in Example 3;

FIG. 10 is a cross-sectional view schematically showing a memory element formed in Example 3.

FIG. 11 is a circuit diagram illustrating a memory configuration according to a fourth exemplary embodiment.

12A is a sectional view schematically showing a state where the magnetizations of the magnetoresistive effect film are parallel, and FIG. 12B is a sectional view schematically showing a state where the magnetizations of the magnetoresistive effect film are antiparallel. .

FIG. 13 is a diagram for explaining a recording / reproducing principle in a conventional magnetoresistive film using an in-plane magnetized film,
(A) and (c) are cross-sectional views schematically showing the state of magnetization when recording information "1" is read, and (b) and (d) are recording information "0". FIG. 3 is a cross-sectional view schematically showing the magnetized state of FIG.

FIG. 14 is a diagram for explaining a recording / reproducing principle in a magnetoresistive effect film using a perpendicular magnetization film, wherein (a) and (c) show the magnetization when reading recorded information “1”. Sectional drawing which shows a state typically, (b) and (d)
FIG. 4 is a cross-sectional view schematically showing a magnetization state when reading recorded information “0”.

[Explanation of symbols]

11, 21 Magnetic layer (detection layer) 12, 22 Non-magnetic layer 13, 23 Magnetic layer (memory layer) 101-109 Magnetoresistive effect film 111 First magnetic body 112 Second magnetic body 113 Third magnetic body 114 Non-magnetic conductor film 114 Non-magnetic dielectric film 117-120 High spin polarization magnetic substance 123 Insulating film 150 Fixed resistance 161 p-type Si substrate 162,163 n-type diffusion region 211-226, 231-242, 511-518,5
21-524, 531-542, 551 Transistor 300, 600 Wiring 311-314, 321-324, 611-614
Write lines 331 to 333, 631 to 633 Bit lines 341 to 343, 641 to 643 Word lines (gate electrodes) 351 to 355, 357 Contact plugs 356 Ground lines 358 Local wiring 411, 412 Power supply 500 Sense amplifier

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01F 10/16 H01F 10/30 10/30 10/32 10/32 H01L 27/10 447 H01L 27/105 G01R 33/06 R

Claims (11)

[Claims] 1. A first magnetic body exhibiting perpendicular magnetization, a non-magnetic conductor film, a second magnetic body exhibiting perpendicular magnetization, a non-magnetic dielectric film, and a third magnetic body exhibiting perpendicular magnetization. Has a structure laminated in this order, the magnetization of the first magnetic body and the magnetization of the third magnetic body are antiparallel to each other, and the first magnetic body and the third magnetic body The magnetoresistive film, wherein the second magnetic body has a relatively small magnetization reversal magnetic field as compared with the first magnetic body. 2. The magnitude of the magnetostatic coupling force exerted from the first magnetic body to the second magnetic body and the magnetostatic coupling force exerted from the third magnetic body to the second magnetic body. The magnetoresistive effect film according to claim 1, wherein the sizes are substantially equal. 3. The interface between the first magnetic body and the non-magnetic conductor film, the interface between the second magnetic body and the non-magnetic conductor film, the second magnetic body and the non-magnetic dielectric film. Interface with
The magnetoresistive film according to claim 1 or 2, wherein a magnetic substance having a high spin polarization is formed on at least one interface between the third magnetic substance and the nonmagnetic dielectric film. 4. The magnetic body having a large spin polarization is formed so as to be symmetric with respect to the second magnetic body in the film thickness direction of the magnetoresistive film. The magnetoresistive film described. 5. The magnetoresistive effect film according to claim 1, wherein the first magnetic body and the third magnetic body have the same composition. 6. The first magnetic body and the third magnetic body have the same shape and size, and the nonmagnetic conductor film and the nonmagnetic dielectric film have the same film thickness. Through 5
The magnetoresistive effect film according to any one of 1 above. 7. The magnetoresistive film according to claim 1, wherein the non-magnetic dielectric film is made of aluminum oxide. 8. The first magnetic body, the second magnetic body, and the third magnetic body are all Gd, Dy, and Tb.
One or more rare earth metal elements and Fe,
The magnetoresistive effect film according to claim 1, which comprises, as a main component, one or more kinds of transition metal elements selected from Co and Ni. 9. The magnetic substance having a large spin polarization is Fe.
The magnetoresistive film according to claim 3, which is made of an alloy of Co and Co. 10. A first magnetic body exhibiting perpendicular magnetization, a non-magnetic conductor film, a second magnetic body exhibiting perpendicular magnetization, a non-magnetic dielectric film, and a third magnetic body exhibiting perpendicular magnetization. Is a method of manufacturing a magnetoresistive effect film having a structure in which they are laminated in this order, and the second magnetic body has a relatively small magnetization reversal magnetic field as compared with the first magnetic body and the third magnetic body. And forming a magnetic body of one of the first magnetic body and the third magnetic body while applying a magnetic field in one direction, and further, a magnetic field direction opposite to that applied when the one magnetic body is formed. A method of manufacturing a magnetoresistive effect film, comprising forming the other magnetic body of the first magnetic body and the third magnetic body while applying a magnetic field in a direction. 11. A magnetoresistive film according to claim 1, means for recording on the magnetoresistive film, and means for reading information recorded on the magnetoresistive film. A memory having: